Hook attachment for hoists



Oct. 6, 1959 F. LowERY HOOK ATTACHMENT FOR HOISTS File d Nov. 26, 1957 5 Sheets-Sheet 3 m M w w mw m Nw 1 A 0 M L a 0 m w m 6 flaw, a r I :Q 2 w 6 5 46, 6 w/ 5 w ,2 /w m 6 4 w z w Kw A x. E 4 2% l6 6 I 4 3 m a 24 4 m 56 5%5 P United States Patent HOOK A'ITACI-HViENT FOR HOISTS Fred Lowery, Republic, Pa.

Application November 26, 1957, Serial No. 699,045

8 Claims. (Cl. 29483) This invention relates to hoist attachments, and it particularly relates to hook attachments adapted to ease the shock of aflixing and releasing a load from a hoist mechanism.

The hoist mechanisms heretofore in generaluse have been eilicient enough in moving a load from one area to another; however, during the actual pick-up or release of the load, they could not be delicately enough manipulated so that the load was usually picked up with a jerk which sometimes overturned or damaged the load, and,

was released with a crash which also tended to damage all but the sturdiest of loads.

It is an object of the present invention to overcome the above and other difficulties by providing a hook attachment which is capable of being easily manipulated to eifect a gentle pick-up and release action.

A further object of this invention is to provide a safety release hoist hook attachment which will automatically release the hook before the load is lifted, if the hoist hook is raised too fast.

A further object of this invention is to provide a safety release on the attachment to insure that the hook will be operated slowly enough to take up all the slack in the hoist lines .without any sudden strain before the actual lifting takes place, and to release the hook should the slack be taken up too fast for safety.

Another object of the present invention is to provide a hook attachment of the above type which is simple in construction and easy to operate.

Other objects of the present invention are to provide an improved hoist attachment, of the character described,

Patented Oct. 6, 1959 is connected to the cross-bar \18 and comprises a rod 22 at each end of the cross-bar 18; these rods "22 being connected, at their upper ends, to" the cross-bar 18 by lock nuts 24 and 26 which are provided on the threaded upper ends of the rods 22 on each side of the cross-bar 18,

after these threaded ends have been inserted through corcounterbores and are limited in their upward movements by the shoulders 29. In this manner, a certain play, or lost motion, is provided between rods 22 and sleeves 28. The sleeves 28 are, themselves, connected into sockets 30 on the upper ends of the respective rods 32. The rods 32 are each slidably positioned within a detent housing =34 having a detent 36 pivoted therein by means of a hinge pin 38. The lower end of each detent housing 34- is integral with a bar 40 connected to a collar 42 by rivets or the like shown at 44. Each rod 32 is adapted to be releasably held against sliding movement by the detent which is adapted to engage within a slot 46 in the corresponding rod 32.

' Slidable on each guide structure of the support 21 is a collar &8 having a piston cylinder 5t} connected thereto. This connection (as best shown in Fig. 4) comprises an inner flange 52 on the collar-48, which flange is clamped between the upper open end of the cylinder 50 and a flange 54 on the upper end of a bushing 56. This bushing 56 is provided with external threads engaged with the internal threads provided at the upper end of cylinder that is easily and economically produced, which is sturdy Fig. 1 is a side elevational view of a hook attachment embodying, the present invention.

, i Fig. 2 is a rear elevational view of the device of Fig. 1.

. Fig. 3 is a side view, similar to Fig. 1, except that it ispartly in elevation and partly in section, and shows the hook in the safety release position.

Fig. 4 is a sectional side view of the device, with some parts shown in elevation, and with the hook in pick-up position.

Fig. 5 is an enlarged, detailed view taken on line 5-5 of Fig. 3.

Fig. 6 is a sectionalview taken on line 6-6 of Fig. 5. Fig. 7 is a diagrammatic view showing the fluid pres sure system.

Referring now in greater detail to the drawings where in similar reference characters refer to similar parts, there is shown a hook attachment, generally designated 10, comprising a swivel ring 12 adapted to be attached to, the chain or cable of a hoist (not shown). The ring 12 is connected to a base 14 which is rotatably mounted on an internal bearing member 16 extending up from a crossbar 18. Ball bearings 20 (note Fig. 4) are provided between bearing member 16, and base 14.

50, as indicated at 58. The bushing 56 is hollow and is provided with a stufing box 60 through which extendsa piston rod 62 attached, at its upper end, to cross-bar 18. The piston rod 62. is provided, at its lower end, with a piston head 64 which is positioned within cylinder 50. A spring 66 extends around the, piston rod 62 between the bushing '56 and head 64 whereby it urges'the piston in a downward direction within the cylinder 50.

The lower open end of the cylinder 50 is received within a socket member 68 and is held therein by threaded engagement, as indicated at 70 in Fig. 4. The socket member 68 is integrally provided with a depending stern 7'2 which is surrounded by a coil spring 74 bearing against the underside of socket member 68, at its upper end, and against collar 42, at its lower end, whereby the spring '74 acts to bias collar 42 downwardly.

The stem 72 is provided with a recess ornotch '76 at its lower end, this recess being arranged to receive the upper portion 78 of a book 80. The hook is pivotally mounted between cars 32 of a bracket 33 by a pivot pin 84. The upper end 78 of the hook 250 is adapted to be retained in the recess 76 by the collar 42 which is biased into its hook-retaining position by spring 74'. However, when the collar 42 is raised, against the force of'spring 74 (as shown in Fig. 3), the hook portion 78 ,wi-llfall,

out and down and the book 80 will turn over into the open, horizontal position (shown in Fig. 3) by the action of gravity. T o replace the hook 86 in its closed position, itis merely necessary to lift up the collar 42, insert the portion 7 8 of the hook into the recess 76, and release the collar 42 which then is forced into its hook-retaining position by spring 74. I V p Extending rearwardly from the socket member 68 is a valve housing 86 having a valve chamber connected by a passage 88 in a boss 89 to a tube 90 which is, in turn, connected to a passage 92 leading into the upper portion of cylinder 50 through an orifice 94 (as shown in Fig. 4-). Also (as shown in Fig.4) there is provided "another passalmon sage 96 connecting with a passage 98 leading into the bottom of cylinder 50.

The valve chamber in housing 86 is designated 100 and includes a valve seat 102. A valve head 104 is movable toward and away from valve seat 102. This movement not only permits the valve to close against the seat 102 but also serves to vary the valve opening so as to vary the amount of fluid passing through the valve. The valve head 104 is mounted on a shaft 106 (as best shown in Fig. 6), and this shaft 106 passes through a bushing 108 in a bearing member 110. A packing member 112 is provided between the bushing 108 and bearing member 11 around shaft 106. A knurled sleeve 114, forming a handle, surrounds the bearing member 110, the shaft 106 passing into this sleeve 114. The end of shaft 106 is tapered and splined, as indicated at 116, and ends just short of the outer end of sleeve 114. A countersunk screw 118 enters a hole in the end of the shaft 106 to keep it'attached to the sleeve 114.

On the other side of valve head 104, the shaft .106 is provided with a threaded portion 120 threadedly engaged in a bushing 122. 'The bushing 122, in addition to being internally threaded, is also externally threaded, as at 124, for engagement with an internally-threaded sleeve portion 126 within the valve housing 86. The bushing 12-2 also has a hexagonal extension 127 integral therewith. Extending axially from extension 127 is an externallythreaded, integral sleeve 129. This sleeve 129 is threaded into an internally-threaded bushing 128 having a bore to receive the shaft 106 and an internally-threaded counterbore to receive sleeve 129. A packing member such as a fiber washer, shown at 133, is positioned between the end of sleeve 129 and the shoulder defining the end of the counterbore in bushing 128.

The shaft 106 extends through the members 127, 128 and 129 into the end of a hollow sleeve 130 similar to sleeve 114. The sleeve 130 is also externally knurled to form a rotatable handle in similar manner to sleeve 114. V

This end of the shaft 106 is also splined and tapered, as at 132, and is provided with a hole to receive the countersunk screw .134. By this construction, either sleeve 114 or sleeve 130 can be rotated to move the shaft 106 axially, this movement being due to the threaded engagement with bushing 122. This axial movement of the shaft 106 acts to move the valve head 104 toward or away from the seat 102, depending on the direction of rotation of either the sleeve 114 or sleeve 130.

The sleeves 114 and 130 are each provided with an annular, wedge-shaped cam, as at 136 and \138 respectively. These cams 136 and 138 are adapted to bear against their respective detents 36 when the device is in its tensioned position, as for example, shown in Fig. 1. In this position, the valve 104 is open and the cams 136 and 138 are under their respective fingers 36 (see Fig. 6). The detents 36 are thereby locked in their respective slots 46 to hold the shafts 32 securely in place so as to prevent any possible pivoting of hook 80. With the valve 104 in closed position, the sleeves 114 and 131 are moved to the right (as viewed in Fig. 6) whereby the cams 136 and 138 are out of alignment with the detents 36 so that the detents are free to leave the slots '46.

The valve housing 86 is further provided with a pump 140 which includes a pump chamber 142 connected to an aligned passage in pump housing 144. Movable in chamber 142 and housing 144 is a pump piston 146-pivotally connected, at its upper end, to a pump handle 148 by means of a hinge pin 149. The handle 148 is itself provided with a lower fork member 150 to which is pivotally connected a pair'of arms 151. These arms -151 are, in turn, pivotally connected at 152 to boss 89.

The pump 140 is connected through passage 153 (best shown in Fig. 7), spring-pressed check valve 154 (best shown in Fig. 6) and passage 156 to passage 88 leading to the upper end of cylinder 50. The pump 140 is also con nected to the underside of the cylinder 50 by a passage 158, spring-pressed check valve 160 (best shown in Fig. 6) and passage 98. The check valve 154 is biased downwardly onto its seat by a spring 162 so that fluid moving upwardly from the pump 140 will force the valve 154 up from its seat and permitflow of the fluid into passage 156. On the other hand, check valve 160 is also biased downwardly toward its seat by spring 164. Since the flow from pump 140 is downwardly toward check valve 160, it will move in the same direction as the bias of spring -'164 and help to maintain the valve 160 in its closed position.

By means of the above-described construction, with valve 104 closed, if the pump handle 148 is manipulated to operate the pump 140, the fluid flow will be through open check valve 154, through passages 88, 90, 92 and 94, and into the upper portion of cylinder 50 above the piston head 64, thereby forcing the cylinder up thus raising the hook and any load thereon. However, if the valve 104 is open, the fluid entering passage 88 through passage 156 will then circulate slowly down through chamber 100, through passage 166, down through passage 96 to an intersection 168. From this intersection 168 the flow is through passage 98 into the underside of cylinder 50'under the piston head 64, whereupon the cylinder will move downwardly if there is a load on it, and also through passage 170, then through open check valve 160 back to the pump which then continues to recirculate it.

In operation, when it is desired to pick up a load, the hoist mechanism is operated so that the hook 80 engages the load to take up the slack in the chain adapted to the load; the valve 104 being first opened so that the fluid can circulate underneath the piston head 64 to permit the piston to move upwardly in-the cylinder 50 against the resistance of spring 66 if the hoist is not stopped as soon as the slack is taken up. Since the hoist chain is attached to the piston rod 62 by means of the swivel ring 12, raising the piston normally causes it to lift the cylinder by means of spring 66 and to thereby take the slack out of the chain and connects the hook to the load.

If the hoist is not stopped when the slack is taken up, or if the hoist is being moved too quickly to stop it .in time, the piston will compress spring 66 and rods 22 will move upward relative to the cylinder in their lostmotion'movements until heads 31 abut against shoulders Whenthis happens, the further upward movement of rods 22 will lift up tubular sleeves 28, rods 32 and bars 40 releasably secured to rods 32 by detents 36. This raises the collar 42 to release the hook stem 78 and permit the hook 80 to pivot shown in Fig. 3 under the force of gravity, to release the load.

If the above-described automatic release does not take place due to proper, gradual movement of the hoist, so that the load is on the hook and the slack is taken out of the hook chain, the hoist mechanism is stopped and the valve 104 is closed, making the hook 80 immovable relative to the swivel ring 12. Then the load is lifted and carried to the desired position. When the desired position is reached, the hoist mechanism is then operated to lower the load to the ground. If desired, the load may .be maneuvered to the ground in the most gentle manner by stopping the hoist just before the load contacts the ground and then, by alternate operation of the pump 140 and'valve 104, slowlylovvering the load down to the ground with hardly a bump; the opening of the valve 104 serving to gently lower the load by permitting it to compress spring 66, while the. closing of the valve, with the corresponding operation. of the pump 140, serves to gently raise the load by pumping fluid into the space between the piston and the upper end of the cylinder.

The pivoting of the hook is illustrated in Figs. 3 and 4.

As shown in these figures of the drawing's,pif a sudden 42 exposes the recess 76 in which is positioned the portion 78 of the hook 80. With the collar 42 no longer in position to retain the portion 7 8 in recess 76, the portion 78 will fall forward and downward out of the recess 76. This will cause the hook 80 to pivot to the horizontal release position shown in Fig. 3. When it is desired to replace the hook 80 in closed positionfit is merely necessary to raise the collar 42 against the force of spring 74, replace the portion 78 in recess 76, and then release the collar 42 to permit it to move back into its springbiased position wherein it latches the hook S0 in place.

Although this invention has been described in considerable detail, such description is intended as being illustrative rather than limiting, since the invention may be variously embodied, and the scope of the invention is to be determined as claimed.

Having thus set forth and disclosed the nature of this invention, what is claimed is:

1. A hook attachment for hoists, compnising a vertical fluid pressure cylinder, a piston in the cylinder, a piston rod secured to the piston and slidably mounted in the upper end of the cylinder, means connected to the upper end of said rod above the cylinder adapted to support it from a hoist line, a coil spring encircling the piston rod inside the cylinder and compressed between the piston and the upper end of the cylinder to urge them away from each other, the opposite ends or the cylinder being provided with fluid passages, a conduit connecting the outer ends of said passages, a normally closed valve in said conduit, a hook support depending from the bottom of the cylinder, a hook movably mounted on said support for movement from a load-supporting position to a load-releasing position, means carried by the cylinder normally locking the hook in load-supporting position but being movable upward to release the hook, and

means connected with said piston rod supporting means and hook-locking means for raising the latter to release the hook it the piston is moved upward a predetermined distance in the cylinder while said valve is open.

2. A hook attachment for hoists, as defined in claim 1, including a manually operable pump communicating with said conduit at opposite sides of the valve for pumping fluid from the lower end to the upper end of the cylinder when the valve is closed.

3. A hook attachment for hoists, as defined in claim 1, in which the central portion of said hook is pivoted on a horizontal axis to its support which has a laterally opening slot for receiving the upper end of the hook, and said hook-locking means includes a collar normally surrounding the hook support and upper end of the hook, said collar being movable upward by the hooklocking means to release the upper end of the hook from said slot.

4. A hook attachment for hoists, comprising a vertical fluid pressure cylinder, a piston in the cylinder, a piston rod secured to the piston and slidably mounted in the upper end of the cylinder, means connected to the upper end of said rod above the cylinder adapted to support it from a hoist line, a coil spring encircling the piston rod inside the cylinder and compressed between the piston and the upper end of the cylinder to urge them away from each other, the opposite ends of the cylinder being provided with fluid passages, a conduit connecting the outer ends of said passages, a normally closed valve in said conduit, a hook support depending from the bottom of the cylinder, a hook movably mounted on said support for movement from a load-supporting position to a load-releasing position, means carried by the cylinder normally locking the hook in load-supporting position but being movable upward to release the hook, and means including a lost motion connection connecting said piston rod supporting means and hook-locking means for raising the latter to release the hook after the piston has been raised far enough in the cylinder while said valve is open to take up said lost motion.

5. A hook attachment for hoists, as defined in claim 4, in which said lost motion connection includes telescoping members connected with said piston rod supporting means and hook-locking means, said members being provided with stops that limit the distance they can be extended.

6. A hook attachment for hoists, comprising a vertical fluid pressure cylinder, a piston in the cylinder, a piston rod secured to the piston and slidably mounted in the upper end of the cylinder, means connected to the upper end of said rod above the cylinder adapted to support it from a hoist line, a coil spring encircling the piston rod inside the cylinder and compressed between the piston and the upper end of the cylinder, the opposite ends of the cylinder being provided with fluid passages, a conduit connecting the outer ends of said passages, a normally closed valve in said conduit, a hook support depending from the bottom of the cylinder, a hook movably mounted on said support for movement from a load-supporting position to a load-releasing position, means carried by the cylinder normally locking the hook in load-supporting position but being movable upward to release the hook, a rod member connected with said piston rod supporting means and movable therewith relative to the cylinder, and retractable means connecting said hook-locking means with said rod member while said valve is open, whereby if the piston is moved upward in the cylinder the hook-locking means will be raised by said rod member and retractable means to release the book.

7. A hook attachment for hoists, as defined in claim 6, including a cam for moving said retractable means into rod member engaging position, and means: for actuating said valve and cam simultaneously.

8. A hook attachment for hoists, comprising a vertical fluid pressure cylinder, a piston in the cylinder, a piston rod secured to the piston and slidably mounted in the upper end of the cylinder, means connected to the upper end of said rod above the cylinder adapted to support it from a hoist line, a coil spring encircling the piston rod inside the cylinder and compressed between the piston and the upper end of the cylinder, the opposite ends of the cylinder being provided with fluid passages, a conduit connecting the outer ends of said passages, a normally closed valve in said conduit, a hook support depending from the bottom of the cylinder, a hook mounted in said support for movement from a load-supporting position to a load-releasing position, means carried by the cylinder normally locking the hook in load-supporting position but being movable upward to release the hook, a rod member connected with said piston rod supporting means and movable therewith relative to the cylinder, said rod member being provided with a stop surface, a pivoted dog carried by said hook-locking means, and means for holding the dog in engagement with said stop surface only while the valve is open, whereby it said piston rod supporting means then is pulled away from the cylinder said rod member and dog will raise said hook-locking means to release the hook.

References Cited in the file of this patent UNITED STATES PATENTS 29,029 Wynblad July 3, 1860 101,681 Towel Apr. 5, 1870 247,829 Johnson Oct. 4, 1881 689,918 Schuhmann Dec. 31, 1901 715,715 Weber Dec. 9, 1902 804,510 Vaughan Nov. 14, 1905 827,795 Foucher Aug. 7, 1906 1,477,866 McGowan Dec. 18, 1923 1,576,204 Maxey Mar. 9, 1926 1,636,209 Bergsten July 19, 1927 2,500,459 Hoover Mar. 14, 1950 2,620,160 Ray Dec. 2, 1952 

